1. Field of the Invention
This invention relates to a transmission for a tractor for transmitting engine power to drive wheels, including a main clutch, a shuttle change speed device, a main change speed device, an auxiliary change speed device and a rear differential arranged in a transmission housing used as a body frame extending longitudinally of the tractor.
2. Description of the Related Art
Conventionally, the tractor transmission noted above is mounted in a housing having a split construction including a portion for accommodating the main clutch and a portion for accommodating the main change speed device, as disclosed in Japanese Patent Publication S61-25933 and Patent Laying-Open Publication H7139624, for example. Such a split construction requires flanges to be formed at connecting portions thereof to enable bolt connection. Thus, the transmission housing has a large construction as a whole, and an unduly large space must be allocated for the transmission housing.
The clutch, shuttle change speed device, main change speed device, auxiliary change speed device and rear differential constructed and arranged separately in the transmission housing increase a space occupied by the transmission, which is obstructive to compactness of the transmission housing.